Twisted chain with increased amounts of metal at points of high wear



y 4, 1965 P. v. LARSEN 3,181,257

TWISTED IN WITH INCREASED AMOU OF ME AT POINTS OF HIGH WEA Filed Aug. 24, 1962 2 Sheets-Sheet l dly/MUS u $071615! May 4, 1965 P v. LARSEN 3,181,257

ASED AMOU TWISTED CHAIN WITH INCRE OF METAL AT POINTS OF HIGH WEA Filed Aug. 24, 1962 2 Sheets-Sheet 2 w fi w United States Patent 3 181,257 TWliSTED CHAN Wllllii INCREASED AMUUNTS til METAL AT PUWTS OF HIGH VJEAR Paul V. Larsen, Portland, Greg, assignor to lEsco Corporation, Portland, Greg, in corporation or @regon Filed Aug. 24, 1962, Ser. No. 219,160 6 Claims. Cl. 37-135) This invention relates to a chain, and, more particularly, to a novel chain element, i.e., a link.

The chain link of the instant invention is employed advantageously, in one environment, in connection with excavating equipment such as dragline buckets. The chain links in such an installation undergo tremendous stresses (pulling, hoisting, dragging along the ground, etc.), and may be as large as 18 or more in length. The problem facing those in this art is to provide chains that have the requisite strength and long life, yet while maintaining the cost at a reasonable figure. These objectives have been imperfectly attained, since wear patterns and stress patterns do not coincide, with the result that replacement occurs when there is still a substantial amount of throwaway metal. It is, therefore, an objective of this invention to provide a chain link that reconciles and achieves these diverse objectives.

Another object of the invention is to provide a novel chain link characterized by non-symmetrical crosssection whereby the wear and stress patterns result in yielding a long lived, strong, economical chain link.

A further object of the invention is to provide a chain link of a unique twisted configuration and one that has special utility in conjunction with excavating equipment, and the like. The inventive link provides an advantageous contour (section) for wearing through contact with abrasive material.

A still further object is to provide a chain made up of substantially identical intermediate links and unique end links which adapt the same for heavy duty work requiring long chain life.

Other objects and advantages, both general and specific, may be seen in the details of construction and operation set down in this specification.

The invention, in conjunction with an illustrative embodiment, is seen in the accompanying drawings, in which-- FIG. 1 is a fragmentary perspective view of a dragline bucket equipped with the inventive chains;

FIG. 2 is a side elevational view of a pair of intermediate links provided in the chains of FIG. 1;

PEG. 3 is a plan elevational view of the links of FIG. 2;

Fit}. 4 is an enlarged sectional view of the link assembly of FIG. 3 and as would be seen along the sight line applied to PEG. 3;

FIG. 5 is an enlarged side elevational view of an intermediate link and which corresponds to the showing of one of the links of FIG. 2;

PEG. 6 is a plan elevational view of the link seen in FIG. 5 and which is substantially the same as FIG. 3 but on enlarged scale;

FlG. 7 is an end elevational view of the link seen in FIGS. 5 and 6;

FIG. 8 is a sectional view taken along the sight line 8--tl applied to FIG. 6; while FIG. 9 is another sectional view taken along the sight line 9-9 of FIG. 6 and in which FIG. 10 is yet another sectional view taken along the sight line i a -10 applied to FIG. 6;

FIG. 11 is a plan elevational view of an end link provided in the inventive chain;

FIG. 12 is a side elevational view, partially broken away, of the link of FIG. 11;

FIG. 13 is an end elevational view of the link of FIGS. 11 and 12;

FIG. 14 is an end elevational view of a complementary end link; and

FIG. 15 is a side elevational view of the end link of FIG. 14.

In the illustration given, the numeral 2t) designates gen erally a dragline bucket equipped with the usual body 21 defining a box or scoop shape and having a forward open end rigidified by an arch 22. The bucket bottom is equipped with a lip 23 to which are secured the usual digger teeth 24. The forward sides of the bucket 20 are equipped with shackles 25 having pins 26 extending generally parallel and on which are mounted rings or pear links 27 to which the drag chains generally designated 28 are secured.

The sides of the bucket provide connections as at 29 for the hoist chains 3th. The hoist chains 30 are separated by the usual spreader bar 31 and are joined at the block 32. Tilting of the bucket is achieved through the conventional cable 33 entrained in a pulley 34 provided as part of the block 32.

A segment of the chain 28 is seen in FIGS. 2-4, wherein identical intermediate links 35 are provided in interlooped relation. A special end loop is provided at 36 (see FIG. 1) and which is shown in larger scale in FIGS. 11-13, the link 35 being shown in larger scale in FIGS. 57.

Reference to FIG. 7 in particular reveals that the end portions and 351) are offset relative to each other, as can 'be more especially appreciated from the construction lines A and B, corresponding in part to the closed curve defined by the line connecting the centers of mass of an infinite number of segments, the segment mass centers being illustrated by the points designated X in FIGS. 8-10. Thus, the lines A and B include portions of the above-mentioned segment mass center curve, the curve portions so included being perpendicular to each other.

In FIG. 5, the construction lines C and D also include portions of the segment mass center curve in the sides of the link at 35c and 35d, respectively, and are arranged at a 45 angle relative to each other. Also, the inventive link as seen in FIGS. 5 and 6 has end halves that are identical, as on opposite sides of the sight line 9-9.

In addition to being twisted, each link 35 has nonsymmetrical transverse sections as in FIGS. 8 and 9, these sectional views being taken perpendicular to the segment mass center curve portions as at B and C. The configuration at the ends 3501 and 35b is seen in FIG. 8, where the exterior of the loop as at 37 is narrower than the inside of the end as at 3B, the cross section being generally trapezoidal. It will also be noted in FIG. 8 that the inside of the ends as at 38 is generally transversely arcuate, i.e., in a plane perpendicular to the segrnent mass center curve portion included in the line B, and this provides the bearing surface for an adjacent link. The adjacent link thus is disposed at right angles, as can be appreciated from FIG. 4, where the foremost link is severed along the'central transverse plane, i.e., the sight line 9-9 of FIG. 6.

In contrast to this, the non-symmetrical cross section along the sides (35c and 35d) has the larger portion of the trapezoidal cross section positioned adjacent the outside of the loop as at 39, with the narrower portion inside as at all (see FIG. 9). Also, the larger wear section terminates in a transversely fiat surface 39, as contrasted to the arcuate surface 38 (compare FIGS. 8 and 9). The surface 39 on each side, as can be seen from FIG. 4, is flat and the two surfaces are selectively available for riding along the ground. Thus, the chains are readily reversible to make the wear uniform. At the area of the sight line i l-1h as applied to FIG. 6, a

3 transformation occurs wherein the cross section is essentially symmetrical about the segment mass center curve, as can be seen in FIG. 10, wherein the crosssectional configuration is designated 41.

Each chain 2% is equipped with an end link 36 inte'rposed between the intermediate links 35 and the pear link or ring 27. Alternatively the end links of the invention may be used as connecting links without the use of pears or rings. It will be appreciated that, in operation, the link 35 will be disposed as shown in FIG. 7 wherein the flat outer side surfaces 39 are parallel with the ground so that the length of the bearing surface 33 of the end 35a is arranged at 45 to both the vertical and horizontal. Thus, the link 36 has at one end a portion 36a which is arranged at 45 to engage the portion 35a but at the other end (foremost in FIG. 13) it presents an end 36b which is horizontal, i.e., the segment mass center curve in the end 36b being horizontal so as to suitably engage the ring or pear link 27. The length of the wear surface in the end link 36 extends in the direction of construction line A of FIG. 13, with the link 36, in operation, being generally disposed as seen in FIG. 13 so as to interfit with the link 35 in the position shown in FIG. 7. The configuration of the link in two elevational views can be seen in FIGS. 11 and 12, where the numerals 36a are applied to the corresponding end of the link 36. The angular relation of the segment mass center curve portions at the ends can be appreciated from the construction lines applied to FIG. 13 and designated A and B-these are separated by an angle of 45. The relationship of the segment mass center curve portions along the sides of the link is 22 /2 and this can be appreciated from a consideration of FIG. 15, where the segment mass center curve portions are designated by the symbols C and D' relative to a complementary end link 42. The link 42 is employed at the power end of the chain 28 (as contrasted to the load end employing the links 36) when it is desired to provide an opposite plane chain. By this is meant that one end link is connected to a ring or pear link that is essentially in a vertical plane, and the other end is connected to a pear link provided in generally a horizontal plane. The link 42, like the link 36, has the end segment mass center curve portions arranged at 45 relative to each other.

It is believed that the elucidation of specific dimensions of a typical intermediate link 35 will be helpful to the understanding of the invention. The dimensions set forth in the table below have to do with the 2" size link, which has an 8" pitch and weighs 26 lbs., the weight per foot of chain link being 39 lbs.

In FIG. the wear surface 391s hatched and the 8" pitch dimension corresponds to the length of the opening seen in FIG. 6. The wear surface 39 is seen in FIGS. 5 and 6 has a length about that of the pitch dimension, i.e., the 8 long opening is measured between the points Table I Symbol: Dimensions in inches A 12% B 7% C 4% D 1 E 2%,

In the operation of the invention, the chains 28 and 30 are attached to a dragline bucket as seen in FIG. 1. The hoist chains are advantageously constructed according to the invention in order to have wear occur on each link abutting the side of the dragline bucket, as contrasted to alternate links, as is the case with conventional chains. Further, this wear occurs at the outside of the sides of the links, which are enlarged, i.e., possessing more wear metal, than the inside. In similar fashion, the insides of the ends of each link are enthickened or enlarged to provide a greater amount of wear material.

i The same arrangement obtains in the end links 36 and 42, as the case may be, where the wear portions or confronting bearing surfaces are equipped with more wear metal than those surfaces or portions in the same cross section remote from the bearing surface. Through the use of the invention, I find that a chain lasts substantially longer in use and that reversal is facilitated to extend the wear life even longer, while at the same time the stresses are properly absorbed and transmitted from link to link.

While in the foregoing specification a detailed descrip tion of an embodiment of the invention has been set down for the purpose of illustration thereof, many variations in the details herein given may be made by those skilled in the art without departing from the spirit and scope of the invention.

I claim:

1. A chain link, comprising an elongated closed loop having an infinite number of integral segments, with a line connecting the centers of mass of said segments being a closed curve, the intersection of said curve with planes perpendicular thereto defining cross sections each having an outer side and an inner side, each link end inner side being arcuate and adapted to enter into bearing relation with another link and being longer than the link end outer side, the intersection of said curve with the central transverse plane of the link defining cross sections each also having an inner side and an outer side, the last-mentioned outer side being longer than the last-mentioned inner side, whereby extensive wear surfaces are provided along the outside or" the link sides and the inside of the link ends, the portion of said curve in one link end being angularly disposed relative to the portion of said curve in the other link end.

2. The link of claim 1 in which the angular disposition is about to provide a reversible link, said wear surfaces along the outsides of the link sides being generally fiat and parallel to each other.

3. The link of claim 1 in which the angular disposition is about 45 4. A link comprising an elongated metal loop adapted to be interlooped with identical links to develop the chain, said loop defining sides and ends, said ends including curved portions, said link, prior to use, having more wear metal at the inside of the ends than the outsides thereof, and more wear metal at the outside of the sides than the insides thereof, the inside surfaces of said ends being transversely arcuate, said curved portions, defined by the segmental mass centers, of said ends, being arranged at about 90 relative to each other.

5. A link comprising an elongated metal loop adapted to be interlooped with identical links to develop the chain, said loop defining sides and ends, said ends including curved portions, said link, prior to use, having more wear metal at the inside of the ends than the outsides thereof, and more wear metal at the outside of the sides than the insides thereof, the inside surfaces of said ends being transversely arcuate, said curved portions, defined by the segmental mass centers, of said ends, being arranged at about 45 relative to each other.

6. In combination, a dragline bucket, comprising a scoop-shaped housing equipped with a pair of spacedapart shackles adjacent the forward end thereof, and a chain connected to each shackle, each chain comprising an end link and a plurality of intermediate links, with the end links being interposed between each shackle and the intermediate links associated therewith, each link comprising an elongated loop having an infinite number of integral segments and providing link ends and link side portions, with a line connecting the centers of mass of said segments being a closed curve, the intersection of said curve with a plane perpendicular thereto in each segment defining a cross section in each segment having an outer side and an inner side, each link inner end side being arcuate and adapted to enter into bearing relation with another link, the intersection of said curve at each 5 link end with a plane perpendicular thereto defining a cross section wherein the link inner side is longer than the link outer side, the intersection of said curve with the center transverse plane of the link defining cross sections each also having an inner and outer side, the last-mentioned outer side being longer than the last-mentioned inner side, said intermediate links being oriented with one of the side portions of each intermediate link generally horizontally to dispose one of said last-mentioned outer sides parallel With the ground, the portion of said curve in one end of each link being angularly related to the portion of said curve in the other end of the lastmentioned link, the said angular disposition being about 90 in each intermediate link and the angular disposition of said end link being about 45.

References Cited by the Examiner UNITED STATES PATENTS 6/82 Wilson 5990 7/82 Bridge 5990 12/37 Harris 59-84 3/43 White 5978 X 3/49 Parker 152-243 9/53 Sennholtz 5990 10/60 Larsen 37-135 FOREIGN PATENTS 3/43 Germany.

BENJAMIN HERSH, Primary Examiner.

15 ROBERT C. RIORDON, Examiner. 

6. IN COMBINATION, A DRAGLINE BUCKET, COMPRISING A SCOOP-SHAPED HOUSING EQUIPPED WITH A PAIR OF SPACEDAPART SHACKLES ADJACENT THE FORWARD END THEREOF, AND A CHAIN CONNECTED TO EACH SHACKLE, EACH CHAIN COMPRISING AN END LINK AND A PLURALITY OF INTERMEDIATE LINKS, WITH THE END LINKS BEING INTERPOSED BETWEEN EACH SHACKLE AND THE INTERMEDIATE LINKS ASSOCIATED THEREWITH, EACH LINK COMPRISING AN ELONGATED LOOP HAVING AN INFINITE NUMBER OF INTEGRAL SEGMENTS AND PROVIDING LINK ENDS AND LINK SIDE PORTIONS, WITH A LINE CONNECTING THE CENTERS OF MASS OF SAID SEGMENTS BEING A CLOSED CURVE, THE INTERSECTION OF SAID CURVE WITH A PLANE PERPENDICULAR THERETO IN EACH SEGMENT DEFINING A CROSS SECTION IN EACH SEGMENT HAVING AN OUTER SIDE AND AN INNER SIDE, EACH LINK INNER END SLIDE BEING ARCUATE AND ADAPTED TO ENTER INTO BEARING RELATION WITH ANOTHER LINK, THE INTERSECTION OF SAID CURVE AT EACH LINK END WITH A PLANE PERPENDICULAR THERETO DEFINING A CROSS SECTION WHEREIN THE LINK INNER SIDE IS LONGER THAN THE LINK OUTER SIDE, THE INTERSECTION OF SAID CURVE WITH THE CENTER TRANSVERSE PLANE OF THE LINK DEFINING CROSS SECTIONS EACH ALSO HAVING AN INNER AND OUTER SIDE, THE LAST-MENTIONED OUTER SIDE BEING LONGER THAN THE LAST-MENTIONED INNER SIDE, SAID INTERMEDIATE LINKS BEING ORIENTED WITH ONE OF THE SIDE PORTIONS OF EACH INTERMEDIATE LINK GENERALLY HORIZONTALLY TO DISPOSE ONE OF SAID LAST-MENTIONED OUTER SIDE PARALLEL WITH THE GROUND, THE PORTION OF SAID CURVE IN ONE END OF EACH LINK BEING ANGULARLY RELATED TO THE PORTION OF SAID CURVE IN THE OTHER END OF THE LASTMENTIONED LINK, THE SAID ANGULAR DISPOSITION BEING ABOUT 90* IN EACH INTERMEDIATE LINK AND THE ANGULAR DISPOSITION OF SAID END LINK BEING ABOUT 45*. 